One day before the election, battles over voters' access to the polls are extending beyond the leafy neighborhoods in coveted battleground states to the concrete and steel of the vast U.S. criminal justice system.

Legal challenges are pending in at least four states — Arizona, Mississippi, Tennessee and Washington — seeking to overturn state laws that ban thousands of prisoners and former prisoners from the polls, even after they serve their sentences.

In other states, experts say laws that allow prisoners and ex-offenders to vote have created uncertainty. Rules vary wildly: In Maine and Vermont, for example, all prisoners can vote. For felons in Alaska and Washington state, only those who have completed their sentences may cast ballots.

The quilt of state laws regulating felons' voting rights is under scrutiny by party leaders, corrections officials and lawyers involved in legal challenges as voter drives sweep the country.

"It's mass confusion," says Nancy Abudu, staff counsel for the voting rights unit of the American Civil Liberties Union. The ACLU is challenging a Tennessee law that requires felons to pay any child support owed and satisfy all restitution requirements related to their sentences before they can vote.

Among the investigations and disputes:

• Alabama prison officials and local activists settled a lawsuit last month challenging a prison-based voter-registration drive. Led by a former inmate, the 3-day-old drive was halted Sept. 18 after the Alabama Republican Party raised concerns about possible fraud. More than 100 inmates signed up to vote. The settlement lets activists hold voter-education sessions but bans them from supplying registration materials.

Alabama law bars voting by offenders convicted of crimes involving "moral turpitude," yet there is little agreement over what that means. "I don't think anybody knows how many (prisoners) could be eligible," Alabama prison spokesman Brian Corbett says.

• Florida election officials have recommended removing 2,134 people from the voting rolls because of disqualifying prior convictions, including an undisclosed number of prisoners. The state plans to review the eligibility of 108,000 more people, Florida Department of State spokeswoman Jennifer Krell Davis says.

• Alaska officials scrambled to determine whether convicted felons who have not been sentenced can vote, following the conviction of U.S. Sen. Ted Stevens, R-Alaska, for concealing gifts. Under current law, all convicted felons are barred from voting until they finish their sentences. Alaska Elections Division Director Gail Fenumiai says the state attorney general's office ruled that Stevens could vote.

• Texas authorities are looking into how 32 death row inmates got voter-registration applications in an apparent attempt to cast absentee ballots. Death row inmates are prohibited from voting. Polk County District Attorney William Lee Hon, a Republican, said the local registrar of voters noticed the inmates included return addresses matching the death row unit in nearby Livingston. "I've never seen anything like this before," Hon says. "Most all of them registered in their own names."

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